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Houdini 13 riverbed upres. Particle multiplication tests for FLIP. Here's an approach that uses DOPs for a particle multiplication effect.

Particle multiplication tests for FLIP

Particle multiplication tests for FLIP. FLIP smorganic/sheeter effect? - Page 3 - Effects - od. FLIP smorganic/sheeter effect? .: Houdini 13 Flip wedges :. .: Houdini 13 Flip wedges :. .: Houdini 13 Flip wedges :. "ILM went even further than this – they modeled the way the air was affected by the water splashes which in turn affected how the water was coming off the waves and splashes as mist and how that mist moved, and how the actions aerated the water and created white water.

.: Houdini 13 Flip wedges :.

This is an outstanding level of realism. “The real selling point or tipping point was when we started building air simulations around all these events,” comments Cofer. “We used our Plume tool, which is our tool for doing smoke and fire simulation. It gives you very detailed air simulations. If you have a ship that breaches up through the ocean, it churns up the water, and there are all these vertices of air rotating under the wings – as it spreads its wings apart, as you go through the evolution of a water droplet, you start with a surface of water, which is meshed, and then splashes, and that atomizes to mist. Cloudy/Murky Liquid. As Julian mentioned, you can prototype this effect with the default Wavetank shelf tool.

Cloudy/Murky Liquid

It sets up the shading network to do all the right steps. The murkiness is generated by a constant tile volume at render time and this is created as Julian mentioned by the fluidtank_fluidinterior object which is assigned to the uniformvolume shader to render this as a volume. The fluidtank_fluidinterior object contains a single polysoup primitive and no volumes. So what gives? FLIP simple texture reprojection.

Setting up a simulation farm. The simplest way to do this is to ssh into another machine and run hbatch with the name of the hip file, then render the appropriate rop output driver.

Setting up a simulation farm

The second simplest way is to write a .cmd file (text file) which opens your scene, and render the rop output driver.. something like "myfile.cmd": mread <myhipfile.hip>render /out/geometry1 then run hbatch like so : hbatch -v myfile.cmd if you want to split it onto multiple machines you're going to have to get much more involved and read the .pdf by Jeff Lait on splitting fluid simulations onto multiple machines: I don't think this applies to particle fluids.. just volume fluids .. not sure). Sand blowing over sand dunes. Water inside of air field - Finished Work. FLIP pressure projection - threading issues.

I've been trying to boil down the optimal performance settings for FLIP simulations, and I've come across a difficult trade-off when it comes to the pressure projection part of the solve.

FLIP pressure projection - threading issues

Running on a dual-socket, 16-core workstation, all other parts of the solve tend to make great use of the full core count. With the preconditioner option on, as expected, it drops to a single core but gets there in the end. With the preconditioner option off, it will get to about 75% CPU usage, and actually takes almost the same time, maybe a hint longer... also expected. The significant thing here is, if I launch Houdini with affinity constrained to 8 cores on a single socket, and 8 threads, the pressure projection with preconditioner off uses 100% CPU on that socket, and completes in around two-thirds of the time... a full 50% speed increase while only using half of the machine.

FLIP leaks through collision geo container - Gatorade Shower Test. Just got a chance to look at this...

FLIP leaks through collision geo container - Gatorade Shower Test

You've got a thin collision object with very fast movement, which is very challenging for a fluid (liquid) solver. The main thing to think here is substepping. Basically you need to give the solver a chance to see as much of the collision motion as possible, which means it needs to solve multiple times per frame, i.e. more than the default of 2 substeps.

Elastic effect on flip fluids on H12. That setup looks good for strain.

Elastic effect on flip fluids on H12

The only big thing missing is the strain isn't being rotated by the velocity field. So if you have a blob that is stretched in X, then rotated 90 degrees, it will still try to restore along the X axis. Gas Velocity Stretch is supposed to fix this, but it is a pretty subtle thing. It's also a bit not-FLIP like because you are keeping a field from frame to frame. Boundry conditions within FLIP using SDF or fields. Hey Everyone I'm looking for a solution to define or a free-slip boundry condition. defined here.

Boundry conditions within FLIP using SDF or fields

Essentially I'm trying to rest two fluids on top of one an other (FluidA ontop of FluidB) and specify the fluidA to have fluidB's velocity only on the boundry. I see with the flipsolver there is enforce_side_boundaries piping into the pressure_solve and again enforce_side_boundaries_viscosity piping into enable_viscosityBoth use the Gas Enforce Boundry DOP. Elastic effect on flip fluids on H12. That setup looks good for strain.

Elastic effect on flip fluids on H12

The only big thing missing is the strain isn't being rotated by the velocity field. So if you have a blob that is stretched in X, then rotated 90 degrees, it will still try to restore along the X axis. FLIP auto resize tool.